Updates to use hssqlppp as a dependency from hackage.

- And removew the hssqlppp dependency as a git submodule.

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "lib/hssqlppp"]
-	path = lib/hssqlppp
-	url = https://github.com/JakeWheat/hssqlppp.git

lib/hssqlppp

@@ -1 +0,0 @@
-Subproject commit 5f7ff2c64e56c42acfd1623fae68e4424c85bac7

stack.yaml

@@ -6,13 +6,10 @@ resolver: lts-5.1
 # Local packages, usually specified by relative directory name
 packages:
 - '.'
-- location: lib/hssqlppp
-  extra-dep: true
-  subdirs:
-  - hssqlppp
 
 # Packages to be pulled from upstream that are not in the resolver (e.g., acme-missiles-0.3)
-extra-deps: []
+extra-deps:
+- hssqlppp-0.6.0
 
 # Override default flag values for local packages and extra-deps
 flags: {}