- Refactoring the 'PackageConstraint' and 'UserConstraint' data
types, and extending their parser/pretty-printer code to support
the proposed qualified constraint syntax (see github issue 3502).

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Don't use installedPkgs for internal library library dirs.

[WIP] Skeleton of new-haddock

Add edit-distance-0.2.2.1 to stack.yaml

Convenience for `stack build`.

Deduplicate packages in the install plan after the solver removes qualifiers.

Parsec parser

Initialize all PackageDescription fields in solver DSL.

Note: we notify only about nbsp at the beginning of the line
nbsp inside fields get just parsed atm

- Also print name of index file

- encode . lenientDecode prepass
- test on 01-index.tar.gz
- few additional files are failing for weird reason

- Initial import of stuff
- Add hackage index parsing test for parsec
- We can parse name and version
- Add generics-sop dep
- Use D.C.Prelude
- Add StructDiff
- Fix integral
- Add Parsec -class
- Add licence parsing
- Free text fields (parsed as ascii atm)
- Better StructDiff
- Parsec BuildType
- Implement VersionRange parser
- Section parsing first steps
- Sketch parseCondTree
- more sec parsing
- Module name
- hs-source-dirs
    ::: composition/0.1/composition.cabal
    ::: composition/0.2/composition.cabal
    ::: composition/0.2.1/composition.cabal
    ::: composition/1.0.0.0/composition.cabal
- PError (Position 20 1) "Unknown section: \"source-repository\""
- Parses condition
- Add some notes, address few comments
- Install alex on linux travis
- Make ParseResult strict state monad
- Use withinVersion
- No warnings
- Move to Distribution.PackageDescription.Parsec.FieldDescr
- extensions
- SourceRepo (sans kind) parsing
- RepoKind
- Few more stuff
- Add Distribution.Compat.Parsec
- We can parse all 'composition*' packages cabal files \o/
- fromUtf8BS
- Clean up abit
- More stuff
- And more stuff
- Traling whitespace :(
- Executables
- Benchmarks
- spaceListField
- Parse flag sections
- a ~ Char,
- tested with
- package description x-fields
- Conditions
- reformat
- Handle old syntax
- More fields
- More stuff
- ^co ok,
- more stuff
- ^c ok
- some of hackage ok
- A-Z ok
- Works [A-al)
- to the h
- rest of Hackage
- Introduce parsec -flag
- Count warnings
- Verify we get not less warnings from parsec parser
- fixup! Introduce parsec -flag
- Warn about old/new syntax and cabal-version
- Invalid UTF warning
- Deprecated fields
- Fix meta
- Move transformers dep under parsec flag
- Add parsec travis job

Better error messages