Separate a description from the synopsis + remove duplicate dependencies versions (DRY)

SJW.cabal

@@ -4,8 +4,12 @@ cabal-version:       >=1.10
 
 name:                SJW
 version:             0.1.2.2
-synopsis:            The Simple Javascript Wrench is a very simple tool to pack several JS «modules» into a single script.
--- description:
+synopsis:            The Simple Javascript Wrench
+description:
+  SJW is a very simple tool to pack several JS «modules» into a single script.
+  It doesn't really do proper compilation work (yet) except resolving the
+  modules dependencies and detecting import loops but it provides each module
+  with an independent execution context in the resulting script.
 homepage:            https://git.marvid.fr/Tissevert/SJW
 -- bug-reports:
 license:             BSD3
@@ -43,11 +47,11 @@ executable sjw
   main-is:             src/Main.hs
   other-modules:       Paths_SJW
   -- other-extensions:
-  build-depends:       attoparsec >= 0.13.2 && < 0.14
-                     , base >=4.9 && <4.15
+  build-depends:       attoparsec
+                     , base
                      , optparse-applicative >= 0.15 && < 0.17
                      , SJW
-                     , text >= 1.2.3 && < 1.3
+                     , text
   default-language:    Haskell2010
   ghc-options:         -Wall