Allow for quoted items in CSV files

This adds support for quoted items in CSV files. Certain data
values (such as InChI formulas) contain commas which will break
the CSV parsing. This now allows for the user to group items in
quotes so that the entire value will be parsed as one item instead
of mistakenly splitting it up.

To illustrate, consider parsing the following before and after this
change to the code:

  inchi,name,boiling_point,melting_point
  "InChI=1S/C2H6O/c1-2-3/h3H,2H2",ethanol,78.37,-114

Now, the inchi formula will be properly parsed.

Change-Id: I83f666de0d13acdbdde88da6ccee8d7ab656f202
Fix spelling error for findMoleculeFromIdentifier()

This fixes a spelling error for the findMoleculeFromIdentifier()
method in the MongoDatabase class.

Change-Id: I47f23bd4cfc2eb226c1341edfc8fd96198e0e3bc
Improve the CSV Import Dialog

This adds improvements to the CSV import dialog. Now, the user
can set up the mapping between the columns in the CSV file and
the identifiers or descriptors that they should represent in the
database. This also allows for the user use different identifier
types (InChI, InChIKey, SMILES, Name, and CAS) instead of just
InChIKey.

Change-Id: Ib68737c5650d2f715c44113b2a02e40ccd0e9e7d
Allow user to change separator character in CsvImportDialog

This adds a field to allow the user to change the separator
character when importing CSV files.

Change-Id: I851138434278a5d7b2b998f7aa82643790bcd453
Allow user to change column names in CSV importer

This adds the ability for the user to change the column name
in the CSV importer dialog. The new name will be displayed in
the preview table and will be used when storing the values in
the database.

Change-Id: Ic9c4b58e863c24a242a7332636b5ed97f4d804c6
Change delimiter line edit to combo box in CSV importer

This changes the delimiter line edit to be a combo box in the
CSV import dialog. This makes it easier for users to specify
the delimiter, especially for difficult characters like tab.

Also adds code to re-parse the file if the delimiter is changed.

Change-Id: I3cf8d669c2e6064c8429c238d541c33e188f9953
Add support for custom delimiters in the CSV importer

This adds support for custom delimiters in the CSV file import
dialog. Now, the dialog allows the user to enter a custom delimiter
in a line edit next to the standard delimiter combo box.

Change-Id: I9a34f2fe206e2d555fbfbb5d8fa93b4a75f58892